Resource substitution and reallocation in a virtual computing environment

ABSTRACT

A host system reallocates resources in a virtual computing environment by first receiving a request to reallocate a first quantity of a first resource type. Next, potential trade-off groups are evaluated and a trade-off group is selected based on the evaluation. The selected trade-off group includes a set of applications running in the virtual computing environment that can use one or more alternate resource types as a substitute for the first quantity of the first resource type. After the selection, the host system reallocates the first quantity of the first resource type from the trade-off group. This reallocation may be made from the trade-off group to either a first application running in the virtual computing environment or the host system itself. If the reallocation is to the host system, then the total quantity of the first resource type allocated to applications running in the virtual computing environment is thereby reduced.

BACKGROUND

The present disclosure relates to virtual computing environments, andmore specifically, to managing resource reallocation through resourcesubstitution in applications running in virtual computing environments.

The use of virtual computing environments has become increasinglypopular in recent years in many areas of business and technology. Insome situations, these virtual computing environments includeapplications running on virtual machines that are each allocatedresources from a shared pool of resources. As used herein, such anapplication may refer to any program or set of programs (e.g., all ofthe programs running on a particular virtual machine). Within virtualcomputing environments, many different types of resources may be subjectto allocation and the allocation of resources may not be equal amongvirtual machines (or their respective applications), even within asingle virtual computing environment. In some situations, thisinequality may be the result of different applications having differentresource requirements (both in terms of resource types and resourcequantities) and the result of the different applications being used fordifferent purposes.

SUMMARY

According to embodiments of the present disclosure, aspects of thedisclosure may include a method, a system, and a computer programproduct for reallocating resources in a virtual computing environment.In some embodiments, a request to reallocate a first quantity of a firstresource type in the virtual computing environment may be received. Atrade-off group may then be selected. The trade-off group may include aset of applications running in the virtual computing environment. Thetrade-off group may have at the first quantity of the first resourcetype allocated to it and may be capable of using one or more alternateresource types as a substitute for the first quantity of the firstresource type. The first quantity of the first resource type may then bereallocated from the trade-off group. In some embodiments, thisreallocation may be made from the trade-off group to a first applicationrunning in the virtual computing environment. Further, in someembodiments, this reallocation may be made from the trade-off group toone or more host systems, whereby a total quantity of the first resourcetype allocated to applications running in the virtual computingenvironment may be reduced.

The above summary is not intended to describe each illustratedembodiment or every implementation of the present disclosure.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The drawings included in the present application are incorporated into,and form part of, the specification. They illustrate embodiments of thepresent disclosure and, along with the description, serve to explain theprinciples of the disclosure. The drawings are only illustrative of someembodiments and do not limit the disclosure.

FIG. 1 illustrates a diagram of a resource substitution matrix, whichincludes several potential resource substitutions that may be utilizedin order to free up scarce resource types in a virtual computingenvironment, consistent with embodiments of the present disclosure.

FIG. 2 illustrates a flowchart of a method for managing resourcereallocation among applications in a virtual computing environment,consistent with embodiments of the present disclosure.

FIG. 3 illustrates a block diagram of an example high level logicalarchitecture of a virtual computing environment including a host systemand multiple virtual machines, consistent with embodiments the presentdisclosure.

FIG. 4 illustrates a flowchart of a method for determining resourcesubstitutions that may be acceptable for a given application, consistentwith embodiments of the present disclosure.

FIG. 5 illustrates a flowchart of a trial allocation method forevaluating potential trade-off groups, consistent with embodiments ofthe present disclosure.

FIG. 6 illustrates a flowchart of a score comparison method forevaluating potential trade-off groups, consistent with embodiments ofthe present disclosure.

FIG. 7 illustrates a diagram of a cloud computing node, consistent withembodiments of the present disclosure.

FIG. 8 illustrates a diagram of a cloud computing environment,consistent with embodiments of the present disclosure.

FIG. 9 illustrates a diagram of abstraction model layers, consistentwith embodiments of the present disclosure.

While the invention is amenable to various modifications and alternativeforms, specifics thereof have been shown by way of example in thedrawings and will be described in detail. It should be understood,however, that the intention is not to limit the invention to theparticular embodiments described. On the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention.

DETAILED DESCRIPTION

Aspects of the present disclosure relate to managing resourcereallocation through resource substitution in applications running invirtual computing environments. While the present disclosure is notnecessarily limited to such applications, various aspects of thedisclosure may be appreciated through a discussion of various examplesusing this context.

The use of virtual computing environments may promote the sharing ofresources. This may occur at least in part because in these environmentsmany clients may share a large server or set of servers, rather thaneach client operating on its own server. This sharing of resources may,in turn, allow for more efficient resource allocation. In order toallocate resources optimally, however, several competing factors mayneed to be considered. For example, in determining the total quantity ofeach resource type that is made available to applications running in agiven virtual computing environment, a balance may need to be struckbetween a desire to avoid waste by minimizing the quantity of freeresources within the virtual computing environment (i.e., to maximizethe percentage of each resource type that is currently allocated toapplications) and a competing desire to ensure that there is notoverutilization of resources (i.e., to avoid running out of one or moreresource types and thereby causing a failure in one or moreapplications), even in situations where resource usage by applicationsmay spike or otherwise be irregularly high. In some situations, thesecompeting goals may create conflict. For example, in situations whereclose to all of the available resources of the virtual computingenvironment are allocated at a given time, risks of overutilization mayarise when more resources are requested, either as new virtual machines(or applications) are initialized or as part of an increase in the usageof resources by existing virtual machines or applications.

In some situations, not all resource types are likely to be at risk ofoverutilization at the same time. That is to say, in some situationswhere there is a resource shortage, it may be for only one resource typeand there may still be an abundance, or at least enough, of otherresource types on hand. This fact may be leveraged. Specifically, thoseresource types for which there is not a shortage may be used as asubstitutes for those resource types for which there is a shortage.

There may be many options for resource substitution within a virtualcomputing environment. Turning now to FIG. 1, shown is a resourcesubstitution matrix 100, which includes several of these potentialresource substitutions. By using the resource substitutions shown inthis matrix, it may be possible to effectively free up certain scarceresource types from applications so that these resources can bereallocated to elsewhere within a virtual computing environment. As usedherein, a scarce resource type may refer to any resource type that avirtual machine (or application) has requested for which there may notbe enough of that resource type freely available within the relevantvirtual computing environment to fulfill the request or at least notenough freely available to fulfill the request without reducing the freequantity of that resource type to an unacceptable level. In theillustrated embodiment, a chart shows five resource types that may beavailable for trade-off to relieve the impact of a situation wherein oneof the other of those five resource types is scarce. These resourcetypes include central processing unit (CPU), for example as measured ingigahertz (GHz); memory, for example as measured in kilobytes (KB);network (i.e., network bandwidth), for example as measured in megabytesper second (MB/Sec); storage, for example as measured in gigabytes (GB);and graphics processing unit (GPU), for example as measured in gigahertz(GHz). In practice, resource substitutions may occur at the individualvirtual machine or application level and may be hardcoded into anapplication or coded in a more flexible manner so as to allow theapplication to respond appropriately to the conditions of the virtualcomputing environment.

In some embodiments, these resource substitutions may allow anapplication to use less of a scarce resource type by using more of otheravailable resource types and/or changing the manner in which it usesthese available resource types. For example, as depicted in substitutionmatrix 100, an application may be able to compensate for a reduction inCPU (i.e., a reallocation of some quantity of CPU from that applicationto another application) by reducing compression of stored to data,thereby increasing its use of storage. Furthermore, in some embodiments,a quantity of a scarce resource type may be obtained from multipleapplications that each make a different resource substitution or set ofresource substitutions. For example, if a given amount of storage needsto be freed up, then one application could free up half of that amountby using more CPU to increase the compression of stored data, and asecond application could free up another half of that amount of storageby increasing its cache size (i.e., using more memory). It is also notedthat some trade-offs may not actually require any additional resourcesin order to make the substitutions discussed herein. For example, anapplication may be able to free up a quantity of a scarce resource typesimply by using the quantities of other resource types allocated to itmore efficiently or in a different manner. In some embodiments wherequantities of scarce resources are freed up in this manner, the users ofthe applications that free up the scarce resources may receive discountson their monetary costs, for example, in the form a reduced monthlyhosting charge. This cost reduction may be proportional to the quantityof scarce resources that are returned.

While a limited number of trade-offs and only five resource types arediscussed in reference to substitution matrix 100, it is contemplatedthat, in some embodiments, more trade-offs may be possible and otherresource types could be considered and used for trade-offs. Moreover,techniques for performing certain trade-offs could be hereafterdiscovered and implemented in the same manner.

Turning now to FIG. 2, shown is a flowchart of a method 200 for managingresource reallocation among applications in a virtual computingenvironment. The method begins at block 201 with a host system withinthe virtual computing environment receiving a request for resources froma monitoring client on a virtual machine running in the virtualcomputing environment. In some embodiments, the virtual machine may benewly established and may be requesting an initial allocation ofresources. In other embodiments, the virtual machine making the requestmay have been previously established and may be requesting additionalresources beyond its initial allocation, either because the applicationsrunning on the virtual machine have increased their need for a certainresource type or because there has been an increase in the number ofapplications running on the virtual machine. Included in the request ofblock 201, is a request for a first quantity of a first, scarce resourcetype. Such a request may include, for example, a request for 500 KB ofRAM where the scarce resource type is memory.

The host system may then attempt to allocate the requested resources tothe requesting virtual machine. However, per block 202, the host systemmay determine that it cannot fulfill the request because one or moreresource types, including the scarce resource type, is exhausted. Insome embodiments, a resource type may be deemed exhausted when thequantity of that resource type that is free within the virtual computingenvironment (i.e., not allocated to a particular virtual machine orapplication) is below a threshold quantity. In some embodiments, thisthreshold quantity may be zero or, more precisely, less than the amountrequested by the requesting virtual machine. Further, in someembodiments, this threshold quantity may be the amount that has beenallocated as reserves for that particular resource type. Such reservesmay be held for a number of contingencies, for example, for anunpredicted spike in resource need.

Next, based on the need for the scarce resource type, the host systemmay, per block 203, make a broadcast to all of the virtual machines thatare running within the virtual computing environment. The broadcast mayinclude both a request for the scarce resource type and an offer of oneor more alternate resource types for trade-off. The alternate resourcetypes for trade-off may include those resource types of which there isdetermined to be more than a threshold quantity. For example, if thereare 500 MB/Sec of free network bandwidth with a reserve threshold of 300MB/Sec of free network bandwidth, then the broadcast may indicate thatthere is 200 MB/Sec of network bandwidth available for trade-off. Insome embodiments, more than one resource type may be indicated asavailable for trade-off at the same time.

Next, per block 204, the host system may collect responses from themonitoring clients on all of the virtual machines running in the virtualcomputing environment. These responses may indicate the extent to whicheach application can use the one or more alternate resource types as asubstitute for the scarce resource. For instance, if the first resourceis CPU, then one virtual machine may indicate that it is running anapplication that could give up a quantity of CPU (e.g, where at leastthat quantity of CPU is currently allocated to it) in exchange foranother quantity of memory (which may be done, as shown in thesubstitution matrix 100 of FIG. 1, by using the increased memory toincrease the cache size for instructions or data, so as to decrease theapplication's need for CPU).

Per block 205, based on these responses from the virtual machines, thehost system may establish a plurality of trade-off groups. As usedherein, a trade-off group may refer to a set of one or more applicationsrunning in the virtual computing environment that can together usequantities of one or more alternate resource types as a substitute forthe desired quantity of a first (e.g., scarce) resource type. An exampletrade-off group might be a single application that can relinquish thedesired quantity of the scarce resource type in exchange for asubstituted quantity of a single alternate resource type. Anotherexample trade-off group might be two applications that can eachrelinquish half of the desired quantity of the scarce resource type inexchange for a first substituted quantity of a first alternate resourcetype (to the first application) and a second substituted quantity of asecond alternate resource type (to the second application). Byestablishing a plurality of trade-off groups, the host system may allowitself a number of options to choose from for a particular resourcereallocation.

Next, per block 206, the host system may evaluate the plurality oftrade-off groups. This evaluation may be done in a number of differentways. Two potential methods for evaluating trade-off groups arediscussed in more detail below in reference to FIGS. 5 and 6. Based onthe evaluation, a trade-off group may be selected, per block 207. Next,per block 208, the desired quantity of the scarce resource type may bereallocated from the applications of the selected trade-off group to therequesting application and, in return, at least one of the one or morealternate resource types may be allocated to the applications of thetrade-off group and used by these applications a substitutes for thefirst resource type.

Some embodiments may function differently than as described in examplemethod 200. For example, it is contemplated that in some embodiments,the alternate resource types that may be used in a resource substitutionby the application giving up the scarce resource type may includeresources that are already allocated to that application (i.e., theapplication may be able to free up a quantity of the scarce resourcetype simply by modifying the manner in which it utilizes the otherresources (of one or more resource types) that it has already beenallocated). Furthermore, in some embodiments, the resource type that issubstituted for may not be a scarce resource type, as the term is usedherein (i.e., other reasons besides scarcity may motivate resourcesubstitution).

Furthermore, in some embodiments, the method 200 may not be initiatedbased on an application's need for more of a scarce resource type, butrather may be initiated in order to reduce the total amount of thescarce resource type that is allocated to applications running in thevirtual computing environment. In such cases, the applications may beasked to perform the trade-off, not for another application, but ratherfor the system as a whole. This may occur, for instance, where the hostsystem determines that too much of the scarce resource type has beenallocated to applications. It may also occur where a portion of theallocated scarce resource type needs to be recalled because the totalavailable quantity of the scarce resource may need to be reducedtemporarily or permanently; for example, the host system may need toreduce the total amount of storage that is allocated to applications inthe virtual computing environment because one of the servers utilized bythe virtual computing environment needs to be shut down for maintenance.

Furthermore, in some embodiments, certain parameters may need to bemaintained at acceptable levels (i.e., at or above thresholds) in orderfor a trade-off group to be selected. This may help to insure that theapplications of the selected trade-off group are not unduly burdened bya resource substitution. Examples of parameters that may need to bemaintained include performance or energy usage (i.e., where a higherparameter value is associated with a lower energy usage). For example,prior to a resource reallocation, a potential trade-off group may beassociated with some acceptable level of performance (as measured foreach individual application or as an average whole). In such an example,in order for the potential trade-off group to be selected, the trade-offgroup must be able to decrease its usage of the scarce resource type andincrease its usage of at least one of the one or more alternateresources, while still maintaining an acceptable performance level(i.e., continuing to be above a threshold performance level).

Turning now to FIG. 3, shown is a block diagram of virtual computingenvironment 300 that may be configured to perform one or more of themethods described herein. The virtual computing environment 300 mayinclude a host system 301 and multiple virtual machines 310, 320, 330,and 340. Within host system 301, a trade-off manager 303 and resourcemanager 302 may be included. The resource manager 302 may serve toallocate resources among the virtual machines of the virtual computingenvironment and receive requests for new or modified allocations (e.g.,reallocations). The trade-off manager 303 may be responsible forcollecting responses to reallocation requests, establishing trade-offgroups based on the responses, and evaluating these trade-off groups.

In the virtual computing environment 300, any number of existing virtualmachines may be included as is represented by virtual machines 1, 2, andn (referenced by numerals 310, 320, and 330, respectively). In addition,one or more newly initialized virtual machines 340 may also be includedin the virtual computing environment 300. Within each virtual machine,may be a monitoring client 312, 322, 332, 342 and an application 311,321, 331, 341. Although it is contemplated that each virtual machine mayinclude more than one application, single applications are depicted herefor the purpose of clarity.

During initialization of the new virtual machine 340, it may bedetermined that certain quantities of certain resource types may need tobe allocated to the new application 341. The new monitoring client 342may send a request 351 for such an allocation to the resource manager302. Upon reviewing the request, the resource manager 302 may determinethat one of the requested resource types is unavailable and maybroadcast its own request 352 to the other virtual machines 312, 322,and 332. This request 352 may include a request for the unavailableresource type and an offer of one or more alternate resource types. Eachmonitoring client 312, 322, 332 may receive the request 352 from theresource manager 302 and, by reviewing the current resource usage andresource requirements of the application running on its respectivevirtual machine, may send a response 353 back to the host system 301indicating the quantity of the scarce resource type that it can give upand the quantities of at least one of the one or more alternateresources that it would require in return. Some virtual machines mayindicate they cannot provide any of the scarce resource type (e.g.,because they need all of the resources that they have been allocated).Based on collecting and analyzing the responses, the trade-off manager303 may establish and evaluate a plurality of trade-off groups. Adesired trade-off group may then be select and a direction 354 may besent to the resource manager 302 indicating the manner in whichresources should be reallocated. The resource manager 302 may thenreallocate the resources among the virtual machines and, per 355,allocate the requested resource type to the new virtual machine 340.

In some embodiments, further communication between the host system 301and the monitoring clients 312, 322, and 332 may aid in identifying andcarrying out these resource substitutions. For example, in a situationwhere virtual machine 310 has agreed to give up a certain quantity of ascarce resource type, communication between a host system 301 andmonitoring client 312 may confirm and finalize the amounts and timing ofthe resources to be traded. Clarifying the timing of a resource trademay also be helpful in other situations; for example, a virtual machinemay specify a certain point in time where a scarce resource type can bepartially freed up for a trade-off. To facilitate this timing aspect ofthe trade-off, a timing factor may be present in certain trade-offagreements (e.g., a monitoring client may agree to free up a quantity ofthe scarce resource type in six minutes).

Turning now to FIG. 4, shown is a flowchart of a method 400 fordetermining potential resource substitutions for a given application.The method may begin at block 401 where a monitoring client of a virtualmachine receives a broadcasted request for a scarce resource type and anoffer of one or more alternate resources types for trade-off. In someembodiments, this broadcast may be the broadcast that is transmitted bythe host system in block 203 of FIG. 2. In response to receiving thebroadcast, the monitoring client may review, per block 402, the usage ofthe scarce resource type by the one or more applications running on thevirtual machine. Next, per block 403, the monitoring client maydetermine potential substitutions of combinations of the one or morealternate resource types that it can make (e.g., using substitutionmatrix 100 of FIG. 1) to allow it to relinquish some of the scarceresource type. For example, if the scarce resource type is storage, thenthe monitoring client might determine that an application running on thevirtual machine can either free up 2 GB of storage by modifying themanner in which it is using its current allocation of memory or free up3 GB of storage by obtaining an extra 20 MB/Sec of the host system'sfree network bandwidth. Next, these potential substitutions may beevaluated, per block 404. When evaluating potential substitutions, themonitoring client may consider characteristics of the application whichwould undergo the substitution. Some characteristics that may be takeninto account may be the effects that the substitution will have on theperformance of the application. For example, relinquishing a quantity ofGPU might not be a problem for a word processing application, but mightbe an issue for a gaming application (where the quality of the graphicsmay have a greater impact on the user's experience). Per 405, based onthese evaluations, the virtual machine may transmit a response back tothe host device indicating the extent to which the one or moreapplications on the virtual machine can use one or more of the alternateresource types as a substitute for the scarce resource type. Thisresponse may also include other information, such as the desirability ofmaking the reallocation and the precise quantity of each alternateresource type that would need to be reallocated to the virtual machinein order to make the substitution feasible. In some embodiments, thisresponse, taken together with responses from other virtual machines inthe monitored environment, may be collected by a host system per block204 of FIG. 2.

While method 400 may be done without user interaction, in someembodiments, user input may be used in determining whether a potentialresource substitution will be acceptable. For example, in someembodiments, feedback from a user of a virtual machine may be used todetermine whether a potential substitution may be made. This may be donein situations where the users may want more control over theirexperiences. Such an ability to control whether a potential resourcesubstitution is acceptable may be significant to a user in a case wherea potential resource substitution may be technically feasible but isstill not acceptable to the user based on the user's preferences orcharacteristics of the application. In addition, it is furthercontemplated, that some or all of the functions ascribed to themonitoring client in the example method 400 may, in some embodiments, beperformed by other components of the virtual machine or may be performedby other aspects of the host system. In situations where the host systemmakes more of the decisions about potential resource substitutions, theresponses transmitted to the host system from the virtual machine mayinclude more raw data rather than analysis. For example, in someembodiments, the monitoring client may only provide to the host systemwith a list of the types of applications that are running on the machineand the resource usage (by type and quantity) by each application. Thehost system may in turn use this information to make detailedevaluations about potential resource substitutions.

Turning now to FIG. 5, shown is a flowchart of trial allocation method500 for evaluating trade-off groups. In some embodiments, this methodmay be used as part of the step of evaluating the plurality of trade-offgroups discussed in reference to block 206 of FIG. 2. The method maybegin at block 501 with a potential trade-off group being chosen by thehost system from among the plurality of trade-off groups. The potentialtrade-off group may be chosen at random or based on some other method oralgorithm. Per block 502, a trial reallocation is performed. As part ofthe trial reallocation, the desired quantity of the scarce resource typeis reallocated from the applications of the trade-off group to therequesting application and the set of one or more alternate resourcetypes to be exchanged are allocated to the potential trade-off group.Per 503, the result of the trial reallocation are measured. Thismeasuring may involve the review of one or more metrics, such asperformance, energy usage, cost, etc.

Next the measured results of the trial reallocation may be compared witha set of criteria. As used herein, criteria may refer to one or morerequirements that must be satisfied. These criteria may relate to all ofthe applications collectively, all of the applications individually, oronly to certain applications affected by the trial reallocation. Examplecriteria may include a requirement that energy usage by the applicationsof the potential trade-off group not increase by more than 15% as aresult of the trade-off. In some embodiments, the criteria may take theform a sliding scale, wherein a less favorable impact on one metricmight be acceptable if there is a more favorable impact on a secondmetric. Per 504, if one or more criterion are failed, then anotherpotential trade-off group may be chosen and steps 501-503 may berepeated. If, however, all of the criterion are met, then the successfultrial allocation may be left in place and the method may end, per block505. In some situations, it may take multiple trials in order to obtaina successful allocation.

Turning now to FIG. 6, shown is a score comparison method 600 forevaluating trade-off groups. Like method 500, in some embodiments,method 600 may be used as part of the evaluating in block 206 of FIG. 2.The method may begin with a potential trade-off group being chosen fromamong the plurality of trade-off groups, per block 601, by a hostsystem. Next, per block 602, a balancing subscore may be calculated forthe potential trade-off group. This balancing subscore may take intoaccount the percentage of each resource type that would be free withinthe virtual computing environment if the potential trade-off group wereto be selected. In some embodiments, a more favorable balancing subscoremay indicate a greater degree of parity among the resource types (e.g.,where each resource type has roughly the same percentage free within thevirtual computing environment).

Next, per block 603, a performance subscore may also be calculated forthe potential trade-off group. This performance subscore may beindicative of the change in performance quality that would occur to eachapplication of the potential trade-off group if this particulartrade-off group were to be selected. In some embodiments, there may beseveral possible different metrics that could be used to quantify achange in performance quality. For example, the host system couldcompare the current usage of each resource type by each application withthe amount of each resource type that would be available to eachapplication after the reallocation occurs. Applications that would haveaccess to lesser quantities of resources after the reallocation wouldtend to negatively impact the performance subscore, particularly wherethe reduced resource type is significant to the performance of thatparticular application (e.g., a reduction in GPU might be particularlysignificant to a gaming application).

Next, per block 604, an energy subscore may also be calculated for thepotential trade-off group. This energy subscore may be based on thechange in energy usage that would occur within the virtual computingenvironment if the potential trade-off group were selected. A lowerenergy usage may be associated with a more favorable energy subscore.Because different types of resource substitutions may result indifferent changes in energy consumption by the applications of thetrade-off groups, energy subscores may vary between potential trade-offgroups. For example, while additional network bandwidth and additionalmemory may both be adequate substitutes for reduced CPU, the addition ofnetwork bandwidth may be the more energy efficient alternative.

Per block 605, the subscores may be combined to generate a finalresource subscore for the potential trade-off group. In someembodiments, not all subscores may be weighted equally in their impacton the final resource score. In addition, while three subscores may beused in this example, it is contemplated that as few as one subscore oras many as a large number of subscores of varying types may be used insome embodiments. Per block 606, a determination may be made as towhether there are any more potential trade-off groups for which a finalresource score has not be calculated. If so, then the next potentialtrade-off group may be chosen and blocks 602-605 may be repeated forthat potential trade-off group. Once a final resource score has beencalculated for all of the relevant potential trade-off groups, thescores may, per block 607, be compared. Based on the results of thecomparison, per block 608, the potential trade-off group with the mostfavorable final resource score may be selected and the resourcereallocation indicated for that trade-off group may be performed.

In some embodiments, the optimization goals represented by the threetypes of subscores described herein may not be the only factorsconsidered in selecting trade-off groups. Other factors or goals asrepresented by any other type of subscore may also be considered, forexample, in the performance of some embodiments of the method 600.

As discussed in more detail below, it is contemplated that some or allof the steps of some of the embodiments of methods described herein maybe performed in alternative orders or may not be performed at all;furthermore, multiple steps may occur at the same time or as an internalpart of a larger process. For example, per blocks 602-605 of method 600of FIG. 6, a balancing subscore, a performance subscore, and an energysubscore, may, in some embodiments, all be calculated as part of thegeneration of a final resource score, rather than as separate stepshaving their own distinct outputs.

It is understood in advance that although this disclosure includes adetailed description on cloud computing, implementation of the teachingsrecited herein are not limited to a cloud computing environment. Rather,embodiments of the present invention are capable of being implemented inconjunction with any other type of computing environment now known orlater developed.

Cloud computing is a model of service delivery for enabling convenient,on-demand network access to a shared pool of configurable computingresources (e.g. networks, network bandwidth, servers, processing,memory, storage, applications, virtual machines, and services) that canbe rapidly provisioned and released with minimal management effort orinteraction with a provider of the service. This cloud model may includeat least five characteristics, at least three service models, and atleast four deployment models.

Characteristics are as follows:

On-demand self-service: a cloud consumer can unilaterally provisioncomputing capabilities, such as server time and network storage, asneeded automatically without requiring human interaction with theservice's provider.

Broad network access: capabilities are available over a network andaccessed through standard mechanisms that promote use by heterogeneousthin or thick client platforms (e.g., mobile phones, laptops, and PDAs).

Resource pooling: the provider's computing resources are pooled to servemultiple consumers using a multi-tenant model, with different physicaland virtual resources dynamically assigned and reassigned according todemand. There is a sense of location independence in that the consumergenerally has no control or knowledge over the exact location of theprovided resources but may be able to specify location at a higher levelof abstraction (e.g., country, state, or datacenter).

Rapid elasticity: capabilities can be rapidly and elasticallyprovisioned, in some cases automatically, to quickly scale out andrapidly released to quickly scale in. To the consumer, the capabilitiesavailable for provisioning often appear to be unlimited and can bepurchased in any quantity at any time.

Measured service: cloud systems automatically control and optimizeresource use by leveraging a metering capability at some level ofabstraction appropriate to the type of service (e.g., storage,processing, bandwidth, and active user accounts). Resource usage can bemonitored, controlled, and reported providing transparency for both theprovider and consumer of the utilized service.

Service Models are as follows:

Software as a Service (SaaS): the capability provided to the consumer isto use the provider's applications running on a cloud infrastructure.The applications are accessible from various client devices through athin client interface such as a web browser (e.g., web-based e-mail).The consumer does not manage or control the underlying cloudinfrastructure including network, servers, operating systems, storage,or even individual application capabilities, with the possible exceptionof limited user-specific application configuration settings.

Platform as a Service (PaaS): the capability provided to the consumer isto deploy onto the cloud infrastructure consumer-created or acquiredapplications created using programming languages and tools supported bythe provider. The consumer does not manage or control the underlyingcloud infrastructure including networks, servers, operating systems, orstorage, but has control over the deployed applications and possiblyapplication hosting environment configurations.

Infrastructure as a Service (IaaS): the capability provided to theconsumer is to provision processing, storage, networks, and otherfundamental computing resources where the consumer is able to deploy andrun arbitrary software, which can include operating systems andapplications. The consumer does not manage or control the underlyingcloud infrastructure but has control over operating systems, storage,deployed applications, and possibly limited control of select networkingcomponents (e.g., host firewalls).

Deployment Models are as follows:

Private cloud: the cloud infrastructure is operated solely for anorganization. It may be managed by the organization or a third party andmay exist on-premises or off-premises.

Community cloud: the cloud infrastructure is shared by severalorganizations and supports a specific community that has shared concerns(e.g., mission, security requirements, policy, and complianceconsiderations). It may be managed by the organizations or a third partyand may exist on-premises or off-premises.

Public cloud: the cloud infrastructure is made available to the generalpublic or a large industry group and is owned by an organization sellingcloud services.

Hybrid cloud: the cloud infrastructure is a composition of two or moreclouds (private, community, or public) that remain unique entities butare bound together by standardized or proprietary technology thatenables data and application portability (e.g., cloud bursting forload-balancing between clouds).

A cloud computing environment is service oriented with a focus onstatelessness, low coupling, modularity, and semantic interoperability.At the heart of cloud computing is an infrastructure comprising anetwork of interconnected nodes.

Referring now to FIG. 7, a schematic of an example of a cloud computingnode is shown. Cloud computing node 10 is only one example of a suitablecloud computing node and is not intended to suggest any limitation as tothe scope of use or functionality of embodiments of the inventiondescribed herein. Regardless, cloud computing node 10 is capable ofbeing implemented and/or performing any of the functionality set forthhereinabove.

In cloud computing node 10 there is a computer system/server 12, whichis operational with numerous other general purpose or special purposecomputing system environments or configurations. Examples of well-knowncomputing systems, environments, and/or configurations that may besuitable for use with computer system/server 12 include, but are notlimited to, personal computer systems, server computer systems, thinclients, thick clients, hand-held or laptop devices, multiprocessorsystems, microprocessor-based systems, set top boxes, programmableconsumer electronics, network PCs, minicomputer systems, mainframecomputer systems, and distributed cloud computing environments thatinclude any of the above systems or devices, and the like. In someembodiments, it is contemplated that computer system/server 12 may beincorporated in one or more of the virtual machines or host systemsdescribed in reference to the present disclosure.

Computer system/server 12 may be described in the general context ofcomputer system-executable instructions, such as program modules, beingexecuted by a computer system. Generally, program modules may includeroutines, programs, objects, components, logic, data structures, and soon that perform particular tasks or implement particular abstract datatypes. Computer system/server 12 may be practiced in distributed cloudcomputing environments where tasks are performed by remote processingdevices that are linked through a communications network. In adistributed cloud computing environment, program modules may be locatedin both local and remote computer system storage media including memorystorage devices.

As shown in FIG. 7, computer system/server 12 in cloud computing node 10is shown in the form of a general-purpose computing device. Thecomponents of computer system/server 12 may include, but are not limitedto, one or more processors or processing units 16, a system memory 28,and a bus 18 that couples various system components including systemmemory 28 to processor 16.

Bus 18 represents one or more of any of several types of bus structures,including a memory bus or memory controller, a peripheral bus, anaccelerated graphics port, and a processor or local bus using any of avariety of bus architectures. By way of example, and not limitation,such architectures include Industry Standard Architecture (ISA) bus,Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, VideoElectronics Standards Association (VESA) local bus, and PeripheralComponent Interconnect (PCI) bus.

Computer system/server 12 typically includes a variety of computersystem readable media. Such media may be any available media that isaccessible by computer system/server 12, and it includes both volatileand non-volatile media, removable and non-removable media.

System memory 28 can include computer system readable media in the formof volatile memory, such as random access memory (RAM) 30 and/or cachememory 32. Computer system/server 12 may further include otherremovable/non-removable, volatile/non-volatile computer system storagemedia. By way of example only, storage system 34 can be provided forreading from and writing to a non-removable, non-volatile magnetic media(not shown and typically called a “hard drive”). Although not shown, amagnetic disk drive for reading from and writing to a removable,non-volatile magnetic disk (e.g., a “floppy disk”), and an optical diskdrive for reading from or writing to a removable, non-volatile opticaldisk such as a CD-ROM, DVD-ROM or other optical media can be provided.In such instances, each can be connected to bus 18 by one or more datamedia interfaces. As will be further depicted and described below,memory 28 may include at least one program product having a set (e.g.,at least one) of program modules that are configured to carry out thefunctions of embodiments of the invention.

Program/utility 40, having a set (at least one) of program modules 42,may be stored in memory 28 by way of example, and not limitation, aswell as an operating system, one or more application programs, otherprogram modules, and program data. Each of the operating system, one ormore application programs, other program modules, and program data orsome combination thereof, may include an implementation of a networkingenvironment. Program modules 42 generally carry out the functions and/ormethodologies of embodiments of the invention as described herein.

Computer system/server 12 may also communicate with one or more externaldevices 14 such as a keyboard, a pointing device, a display 24, etc.;one or more devices that enable a user to interact with computersystem/server 12; and/or any devices (e.g., network card, modem, etc.)that enable computer system/server 12 to communicate with one or moreother computing devices. Such communication can occur via Input/Output(I/O) interfaces 22. Still yet, computer system/server 12 cancommunicate with one or more networks such as a local area network(LAN), a general wide area network (WAN), and/or a public network (e.g.,the Internet) via network adapter 20. As depicted, network adapter 20communicates with the other components of computer system/server 12 viabus 18. It should be understood that although not shown, other hardwareand/or software components could be used in conjunction with computersystem/server 12. Examples, include, but are not limited to: microcode,device drivers, redundant processing units, external disk drive arrays,RAID systems, tape drives, and data archival storage systems, etc.

Referring now to FIG. 8, illustrative cloud computing environment 50 isdepicted. As shown, cloud computing environment 50 comprises one or morecloud computing nodes 10 with which local computing devices used bycloud consumers, such as, for example, personal digital assistant (PDA)or cellular telephone 54A, desktop computer 54B, laptop computer 54C,and/or automobile computer system 54N may communicate. Nodes 10 maycommunicate with one another. They may be grouped (not shown) physicallyor virtually, in one or more networks, such as Private, Community,Public, or Hybrid clouds as described hereinabove, or a combinationthereof. This allows cloud computing environment 50 to offerinfrastructure, platforms and/or software as services for which a cloudconsumer does not need to maintain resources on a local computingdevice. It is understood that the types of computing devices 54A-N shownin FIG. 8 are intended to be illustrative only and that computing nodes10 and cloud computing environment 50 can communicate with any type ofcomputerized device over any type of network and/or network addressableconnection (e.g., using a web browser).

Referring now to FIG. 9, a set of functional abstraction layers providedby cloud computing environment 50 (FIG. 8) is shown. It should beunderstood in advance that the components, layers, and functions shownin FIG. 9 are intended to be illustrative only and embodiments of theinvention are not limited thereto. As depicted, the following layers andcorresponding functions are provided:

Hardware and software layer 60 includes hardware and softwarecomponents. Examples of hardware components include mainframes, in oneexample IBM® zSeries® systems; RISC (Reduced Instruction Set Computer)architecture based servers, in one example IBM pSeries® systems; IBMxSeries® systems; IBM BladeCenter® systems; storage devices; networksand networking components. Examples of software components includenetwork application server software, in one example IBM WebSphere®application server software; and database software, in one example IBMDB2® database software. (IBM, zSeries, pSeries, xSeries, BladeCenter,WebSphere, and DB2 are trademarks of International Business MachinesCorporation registered in many jurisdictions worldwide).

Virtualization layer 62 provides an abstraction layer from which thefollowing examples of virtual entities may be provided: virtual servers;virtual storage; virtual networks, including virtual private networks;virtual applications and operating systems; and virtual clients. Variousaspects of the present disclosure are directed toward monitoring thestatus of deployment components within the virtualization layer 62 usingdeployment patterns, as discussed in more detail herein.

In one example, management layer 64 may provide the functions describedbelow. Resource provisioning provides dynamic procurement of computingresources and other resources that are utilized to perform tasks withinthe cloud computing environment. Metering and Pricing provide costtracking as resources are utilized within the cloud computingenvironment, and billing or invoicing for consumption of theseresources. In one example, these resources may comprise applicationsoftware licenses. Security provides identity verification for cloudconsumers and tasks, as well as protection for data and other resources.User portal provides access to the cloud computing environment forconsumers and system administrators. Service level management providescloud computing resource allocation and management such that requiredservice levels are met. In some embodiments, such resource allocationand management may take the form of one or more of the methods describedherein (e.g., methods for managing resource substitution andreallocation within virtual computing environments). Service LevelAgreement (SLA) planning and fulfillment provide pre-arrangement for,and procurement of, cloud computing resources for which a futurerequirement is anticipated in accordance with an SLA.

Workloads layer 66 provides examples of functionality for which thecloud computing environment may be utilized. Examples of workloads andfunctions which may be provided from this layer include: mapping andnavigation; software development and lifecycle management; virtualclassroom education delivery; data analytics processing; and transactionprocessing; and mobile desktop.

The present invention may be a system, a method, and/or a computerprogram product. The computer program product may include a computerreadable storage medium (or media) having computer readable programinstructions thereon for causing a processor to carry out aspects of thepresent invention.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program instructions for carrying out operations ofthe present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, or either source code or object code written in anycombination of one or more programming languages, including an objectoriented programming language such as Smalltalk, C++ or the like, andconventional procedural programming languages, such as the “C”programming language or similar programming languages. The computerreadable program instructions may execute entirely on the user'scomputer, partly on the user's computer, as a stand-alone softwarepackage, partly on the user's computer and partly on a remote computeror entirely on the remote computer or server. In the latter scenario,the remote computer may be connected to the user's computer through anytype of network, including a local area network (LAN) or a wide areanetwork (WAN), or the connection may be made to an external computer(for example, through the Internet using an Internet Service Provider).In some embodiments, electronic circuitry including, for example,programmable logic circuitry, field-programmable gate arrays (FPGA), orprogrammable logic arrays (PLA) may execute the computer readableprogram instructions by utilizing state information of the computerreadable program instructions to personalize the electronic circuitry,in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the block may occur out of theorder noted in the figures. For example, two blocks shown in successionmay, in fact, be executed substantially concurrently, or the blocks maysometimes be executed in the reverse order, depending upon thefunctionality involved. It will also be noted that each block of theblock diagrams and/or flowchart illustration, and combinations of blocksin the block diagrams and/or flowchart illustration, can be implementedby special purpose hardware-based systems that perform the specifiedfunctions or acts or carry out combinations of special purpose hardwareand computer instructions.

The descriptions of the various embodiments of the present disclosurehave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of the describedembodiments. The terminology used herein was chosen to best explain theprinciples of the embodiments, the practical application or technicalimprovement over technologies found in the marketplace, or to enableothers of ordinary skill in the art to understand the embodimentsdisclosed herein.

What is claimed is:
 1. A computer program product for managing resourcesof a plurality of resource types in a virtual computing environmenthaving a plurality of applications running therein, the computer programproduct comprising a computer readable storage medium having programinstructions embodied therewith, the program instructions executable bya computer to cause the computer to: receive, by the virtual computingenvironment, a request to reallocate a first quantity of a firstresource type of the plurality of resource types; select, by the virtualcomputing environment, a trade-off group, the trade-off group includinga set of applications of the plurality of applications, the trade-offgroup having at least the first quantity of the first resource typeallocated to it, and the trade-off group being capable of using one ormore alternate resource types as a substitute for the first quantity ofthe first resource type; and reallocate, by the virtual computingenvironment, the first quantity of the first resource type from thetrade-off group, wherein the trade-off group is selected from aplurality of trade-off groups, and wherein, as part of the selecting thetrade-off group, the program instructions are executable by the computerto further cause the computer to: perform, by the virtual computingenvironment, a first trial reallocation including reallocating the firstquantity of the first resource type from a potential trade-off group ofthe plurality of trade-off groups to a first application andreallocating a second set of one or more alternate resource types to thepotential trade-off group; measure, by the virtual computingenvironment, results of the performing the first trial reallocation;determine, by the virtual computing environment, that the results of theperforming the first trial reallocation fail to meet at least onecriterion of a set criteria; perform, by the virtual computerenvironment, a second trial reallocation including the reallocating thefirst quantity of the first resource type from the trade-off group tothe first application and reallocating the one or more alternateresource types to the trade-off group; measure, by the virtual computingenvironment, results of the performing the second trial reallocation;and determine, by the virtual computing environment, that the results ofthe performing the second trial reallocation satisfy the set ofcriteria.
 2. The computer program product of claim 1, wherein, prior tothe reallocation, the trade-off group is associated with an acceptablelevel of at least one parameter, and wherein, in response to thereallocation, the trade-off group decreases its usage of the firstresource type and increases its usage of the one or more alternateresource types while maintaining the acceptable level of the at leastone parameter.
 3. The computer program product of claim 2, wherein theat least one parameter is selected from the group consisting ofperformance and energy usage.
 4. The computer program product of claim1, wherein each application of each of the plurality of trade-off groupsincludes one or more characteristics, and wherein the set of criteria isbased at least in part on the one or more characteristics.